With the proliferation of the Internet, there has been a corresponding increase in the growth of the on-line dissemination of digital content such as, for example, MP3 music files and audio/visual files, such as, for example, MPEG files. A concern of the owners of any intellectual property rights; such as copyrights, in digital content that is sold via the Internet, is the prevention of the unauthorised copying and further distribution of the digital works. Attempts have been made, via the use of various encryption technologies, to distribute in a secure form digital content. However, once digital content has been legitimately decrypted very little can be done to prevent unauthorised copying and distribution of the digital content.
It is an object of the present invention at least to mitigate some of the above problems.